Water-mixed fuel, additive-modified fuel oil, additive, and methods for production of the same

ABSTRACT

[Object] To provide an additive that can achieve uniform dispersion of oil and water to improve combustion efficiency and also can stabilize the uniform dispersion of oil and water for a long period of time, an additive-modified fuel oil and a water-mixed fuel obtained by addition of the additive, and methods of producing them. 
     [Solution] A method of producing an additive that is used for generating a water-mixed fuel or a water-unmixed modified fuel oil by being added to a fuel oil includes the steps of: dissolving a relatively low molecular weight alcohol in a fatty acid or a relatively high molecular weight alcohol to generate an intermediate product  1 ; adding a surfactant to the intermediate product  1  to generate an intermediate product  2 ; adding only an amine compound or both an amine compound and ethylene glycol to the intermediate product  2  to generate an intermediate product  3 ; and adding aqueous ammonia or gaseous ammonia to the intermediate product  3  to generate a desired additive.

TECHNICAL FIELD

The present invention relates to a water-mixed fuel, a water-unmixed modified fuel oil that can be formed into a water-mixed fuel by addition of water, an additive added thereto, and methods of producing them.

BACKGROUND ART

Water-mixed fuels, which are fuel oils mixed with water, have attracted attention from the viewpoints of, for example, depletion of petroleum resources and environmental problems caused by the use of petroleum. It is already publicly known that the water-mixed fuels provide combustion efficiency comparable to that of combustion of only the fuel oils, and various types of water-mixed fuels have been proposed.

Technologies relating to conventional water-mixed fuels are described in, for example, Patent Documents 1 to 4.

CITATION LIST Patent Literature

-   Patent Document 1: JP-A-2008-81740, “METHOD OF PRODUCING EMULSION     FUEL BY MIXING WATER AND COMBUSTIBLE OIL IN FINE PARTICLE STATE,     APPARATUS FOR PRODUCING EMULSION FUEL, AND EMULSION FUEL” -   Patent Document 2: JP-A-2007-284527, “HEAVY OIL ADDITIVE” -   Patent Document 3: JP-A-2006-111666, “METHOD OF PRODUCING EMULSION     FUEL, APPARATUS FOR PRODUCING EMULSION FUEL, AND EMULSION FUEL-USING     EQUIPMENT EQUIPPED WITH THE APPARATUS FOR PRODUCING EMULSION FUEL” -   Patent Document 4: JP-A-2004-67913, “METHOD OF PRODUCING WATER     EMULSION FUEL”

However, conventional water-mixed fuels have problems such as unstable combustion, instability during long term storage due to, for example, oil/water separation, and a lack of uniform dispersion between oil and water, and therefore are not capable of sufficiently enduring practical use.

SUMMARY OF INVENTION Technical Problem

Accordingly, it is an object of the present invention to provide an additive that can achieve uniform dispersion of oil and water to improve combustion efficiency and also can stabilize the uniform dispersion of oil and water for a long period of time, an additive-modified fuel oil and a water-mixed fuel obtained by addition of the additive, and methods of producing them.

Solution to Problem

In order to solve the above-mentioned problems, the method of producing an additive of the present invention includes the following constitution. That is, the method produces an additive that is used for generating a water-mixed fuel or a water-unmixed modified fuel oil by being added to a fuel oil and is characterized by including the steps of: dissolving a relatively low molecular weight alcohol in a fatty acid or a relatively high molecular weight alcohol to generate an intermediate product 1; adding a surfactant to the intermediate product 1 to generate an intermediate product 2; adding only an amine compound or both an amine compound and ethylene glycol to the intermediate product 2 to generate an intermediate product 3; and adding aqueous ammonia or gaseous ammonia to the intermediate product 3 to generate a desired additive.

Herein, as the fuel oil, gasoline, kerosene, light oil, heavy oil A, heavy oil B, heavy oil C, crude oil, vegetable oil, animal oil, waste oil, and papermaking effluent black liquor can be used.

The fatty acid is preferably any of butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, α-linolenic acid, stearidonic acid, eicosapentaenoic acid, docosahexaenoic acid, linoleic acid, γ-linolenic acid, dihomo-γ-linolenic acid, arachidonic acid, oleic acid, erucic acid, maleic acid, fumaric acid, and dodecanoic acid, or an ester thereof.

The relatively high molecular weight alcohol is preferably pentanol, hexanol, undecanol, dodecanol, or tridecanol.

The relatively low molecular weight alcohol is preferably methanol, ethanol, propanol, or ethylene glycol.

The surfactant is preferably polyoxyalkylene branched decyl ether, polyoxyethylene monolaurate, polyoxyethylene monooleate, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene oleylamine, polyoxyethylene stearylamine, coconut oil fatty acid diethanol amide, or oleic acid diethanol amide.

The amine compound is preferably monoethanolamine, isopropanolamine, n-propanolamine, or cyclohexylamine.

The mixing ratio of the fatty acid or the relatively high molecular weight alcohol, the relatively low molecular weight alcohol, the surfactant, only the amine compound or both the amine compound and ethylene glycol, and aqueous ammonia or gaseous ammonia is preferably 1:1.0 to 1.5:0.0 to 0.7:0.3 to 0.9:0.001 to 0.7 (molar concentration), more preferably 1:1.1 to 1.4:0.4 to 0.6:0.4 to 0.8:0.003 to 0.2 (molar concentration).

The additive of the present invention is an additive produced by the above-described method and is characterized in that the raw materials at least include a fatty acid or a relatively high molecular weight alcohol; a relatively low molecular weight alcohol; a surfactant; only an amine compound or both an amine compound and ethylene glycol; and aqueous ammonia or gaseous ammonia.

The method of producing an additive-modified fuel oil of the present invention is a method of producing a water-unmixed modified fuel oil that can be formed into a water-mixed fuel by addition of water and is characterized by including the step of adding the above-described additive to a fuel oil to generate a desired additive-modified fuel oil.

The mixing ratio of the additive and the fuel oil is preferably 0.03 to 0.3:1 (volume), more preferably 0.05 to 0.2:1 (volume).

The additive-modified fuel oil of the present invention is an additive-modified fuel oil produced by the above-described method and is characterized in that the raw materials of the additive at least include a fatty acid or a relatively high molecular weight alcohol; a relatively low molecular weight alcohol; a surfactant; at least one of an amine compound and ethylene glycol; and aqueous ammonia or gaseous ammonia.

The method of producing a water-mixed fuel of the present invention is characterized by including the step of adding water to the above-described additive-modified fuel oil to generate a desired water-mixed fuel.

The mixing ratio of water and the additive-modified fuel oil is preferably 0.1 to 0.8:1 (volume), more preferably 0.2 to 0.6:1 (volume).

The water-mixed fuel of the present invention is a water-mixed fuel produced by the above-described method and is characterized in that the raw materials of the additive at least include a fatty acid or a relatively high molecular weight alcohol; a relatively low molecular weight alcohol; a surfactant; at least one of an amine compound and ethylene glycol; and aqueous ammonia or gaseous ammonia.

Advantages

In the water-mixed fuel obtained by the present invention, appropriate addition of the additive realizes uniform dispersion of oil and water to improve combustion efficiency and also stabilizes the uniform dispersion of oil and water for a long period of time. In addition, appropriate addition of the additive allows a water-unmixed modified fuel oil to be transported and stored, resulting in enhanced convenience.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an explanatory diagram illustrating a flow of generating a water-mixed fuel.

FIG. 2 is an explanatory diagram illustrating an example of producing an additive.

FIG. 3 is an explanatory diagram illustrating an example of producing an additive-modified fuel oil.

FIG. 4 is an explanatory diagram illustrating an example of producing a water-mixed fuel.

FIG. 5 is a photograph of experimental results showing differences of water-mixed fuels in beakers.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described below based on examples shown in the drawings. Note that embodiments are not limited to those shown below and can be appropriately modified in the design using conventionally known technologies such as those described in the above-mentioned patent documents within a range not departing from the spirit of the present invention.

FIG. 1 is an explanatory diagram illustrating a flow of generating a water-mixed fuel.

The present inventor has found the fact that uniform dispersion of oil and water of a water-mixed fuel and long-term stability of the uniform dispersion can be achieved by adding a specific additive to the fuel oil.

Herein, the term “fuel oil” refers to general combustible oils such as gasoline, kerosene, light oil, heavy oil A, heavy oil B, heavy oil C, crude oil, vegetable oil, animal oil, waste oil, and papermaking factory waste oil (black liquor). The water-mixed fuel of the present invention is a mixture of the fuel oil and predetermined amounts of water and the additive according to the present invention.

The method of producing the additive is as follows:

First, an intermediate product 1 is generated by dissolving a relatively low molecular weight alcohol in a fatty acid or a relatively high molecular weight alcohol. The fatty acid may be a mixture of a fatty acid and a fatty acid ester, as well as a fatty acid alone.

Herein, the relatively high molecular weight alcohol is a liquid having a higher alkyl group and refers to, for example, pentanol, hexanol, undecanol, dodecanol, or tridecanol and may be an alcohol having a side chain, such as iso-compounds.

The relatively low molecular weight alcohol is a liquid having a lower alkyl group and refers to, for example, methanol, ethanol, propanol, or ethylene glycol.

The fatty acid refers to monounsaturated to polyunsaturated fatty acids that can dissolve methanol, ethanol, or propanol, and examples thereof include butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, α-linolenic acid, stearidonic acid, eicosapentaenoic acid, docosahexaenoic acid, linoleic acid, γ-linolenic acid, dihomo-γ-linolenic acid, arachidonic acid, oleic acid, erucic acid, maleic acid, fumaric acid, and dodecanoic acid.

Then, an intermediate product 2 is generated by adding a surfactant to the intermediate product 1 and sufficiently stirring the mixture to obtain a certain condition.

The reaction temperature during the generation of the intermediate product 2 is preferably 0 to 40° C., and the condition for the stirring is preferably within a range of low incorporation of air.

Herein, the surfactant refers to, for example, a nonionic polyether surfactant (e.g., polyoxyalkylene branched decyl ether, polyoxyethylene monolaurate, polyoxyethylene monooleate, or polyoxyethylene polyoxypropylene alkyl ether) or a nonionic amide surfactant (e.g., polyoxyethylene oleylamine, polyoxyethylene stearylamine, coconut oil fatty acid diethanol amide, or oleic acid diethanol amide).

Then, an intermediate product 3 is generated by adding only an amine compound or both an amine compound and ethylene glycol to the intermediate product 2 and sufficiently stirring the mixture to obtain a certain condition.

Since heat is produced during the generation of the intermediate product 3, it is preferable to sufficiently stir the mixture so that the reaction uniformly proceeds.

Here, the amine compound refers to, for example, monoethanolamine, diethanolamine, or propanolamine.

Then, an additive of the present invention is generated by adding aqueous ammonia or gaseous ammonia to the intermediate product 3 and sufficiently stirring the mixture to obtain a certain condition.

Since addition of an excessive amount of gaseous ammonia turns the additive into a gel, it is preferable to appropriately adjust the amount of the gaseous ammonia.

Since it is possible to mix raw materials in various combinations, an optimum mixing ratio differs depending on the raw materials, but the following values can be used as rough ratio standard:

(Fatty acid or relatively high molecular weight alcohol):(relatively low molecular weight alcohol):(surfactant):(only amine compound or both amine compound and ethylene glycol):(aqueous ammonia or gaseous ammonia) is 1:1.0 to 1.5:0.0 to 0.7:0.3 to 0.9:0.001 to 0.7 (molar concentration).

More preferably, (fatty acid or relatively high molecular weight alcohol):(relatively low molecular weight alcohol):(surfactant):(only amine compound or both amine compound and ethylene glycol):(aqueous ammonia or gaseous ammonia) is 1:1.1 to 1.4:0.4 to 0.6:0.4 to 0.8:0.003 to 0.2 (molar concentration).

EXAMPLES Example

An example of producing an additive is as follows:

As shown in FIG. 2, an additive can be produced by mixing and stirring methanol (3.94 mol) with oleic acid (2.50 mol) and then sequentially mixing and stirring with polyoxyalkylene branched decyl ether (0.19 mol), isopropylamine (0.70 mol), ethylene glycol (0.55 mol), and gaseous ammonia (0.01 mol).

The method of modifying a fuel oil by the additive is as follows:

The above-described additive according to the present invention is mixed and stirred with a fuel oil, such as gasoline, kerosene, light oil, heavy oil A, heavy oil B, heavy oil C, crude oil, vegetable oil, animal oil, waste oil, or papermaking factory waste oil (black liquor), to generate an additive-modified fuel oil.

This additive-modified fuel oil may be stored in this form to generate a water-mixed fuel by addition of water when it is used.

The types of raw materials of the additive, such as fatty acid, are appropriately determined according to the type of the fuel oil to which the additive is added. As a result, the amount of water to be added, described below, can be optimized.

The necessary amount of the additive varies depending on the type of the fuel oil and the type of the surfactant used in the additive, but the following values can be used as rough ratio standard:

(additive):(fuel oil)=0.03 to 0.3:1 (volume); and

more preferably,

(additive):(fuel oil)=0.05 to 0.2:1 (volume).

Example

An example of producing an additive-modified fuel oil is as follows:

As shown in FIG. 3, an additive-modified fuel oil can be produced by mixing and stirring the additive (3 L, volume: 23) with kerosene (10 L, volume: 77).

The method of preparing a water-mixed fuel of the additive-modified fuel oil is as follows:

The above-described additive-modified fuel oil according to the present invention is mixed and stirred with water to generate a water-mixed fuel.

Since incorporation of air during the stirring has a risk of causing an explosive gas mixture, the stirring is preferably performed under conditions not incorporating air at all.

The generated fuel is liquefied or gelified depending on the ratio of water. If the ratio of water is too high, a decrease in combustion temperature or combustion calorie occurs. For example, when the fuel is used for a gas turbine, water to be added is preferably feed-water for boiler.

Note that when the mixing ratio of raw materials of the additive is not sufficiently appropriate or when the reaction of the additive is not sufficiently accelerated, a white precipitate may be generated after the addition of water, but this does not interfere with combustion.

As the amount of water to be added, from the viewpoints of combustion efficiency and economic efficiency, the following values can be used as rough ratio standard:

(water):(additive-modified fuel oil)=0.1 to 0.8:1 (volume), and

more preferably,

(water):(additive-modified fuel oil)=0.2 to 0.6:1 (volume).

Example

An example of producing a water-mixed fuel is as follows:

As shown in FIG. 4, a water-mixed fuel can be produced by mixing and stirring water (5 L, volume: 28) with kerosene (13 L, volume: 72).

FIG. 5 is a photograph of experimental results showing degrees of uniformity in water-mixed fuels.

The ratio of additive increases from the leftmost beaker to the right, and the ratios of kerosene, water, and additive are (kerosene):(water):(additive)=63:31:6, 59:29:12, 56:27:17, and 53:26:21.

In general, the conditions of a water-mixed fuel vary depending on the mixing ratio of oil and water and on the addition ratio of the additive. However, in the water-mixed fuel according to the present invention, though cloudiness increases with the addition ratio of water and decrease the transmittance, the uniformly mixed state of oil and water is maintained without causing separation into two layers or separation of grains. Furthermore, the uniformly mixed state is stably maintained for a long period of time.

INDUSTRIAL APPLICABILITY

The present invention is practical as various fuels, for example, fuels for various types of boilers such as hot air boilers, hot water boilers, and steam boilers and for diesel engines of, e.g., generators, agricultural machines, automobiles, and ships. Thus, the present invention has a high industrial utility value. 

1. A method of producing an additive to be used for generating a water-mixed fuel or a water-unmixed modified fuel oil by being added to a fuel oil and for stably maintaining a uniformly mixed state for a long period of time without causing separation between oil and water, the method comprising the steps of: dissolving a relatively low molecular weight alcohol in a fatty acid or a relatively high molecular weight alcohol to generate an intermediate product 1; adding a surfactant to the intermediate product 1 to generate an intermediate product 2; adding only an amine compound or both an amine compound and ethylene glycol to the intermediate product 2 to generate an intermediate product 3; and adding aqueous ammonia or gaseous ammonia to the intermediate product 3 to generate a desired additive.
 2. The method of producing an additive according to claim 1, wherein the fuel oil is any of gasoline, kerosene, light oil, heavy oil A, heavy oil B, heavy oil C, crude oil, vegetable oil, animal oil, waste oil, and papermaking effluent black liquor.
 3. The method of producing an additive according to claim 1, wherein the fatty acid is any of butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, α-linolenic acid, stearidonic acid, eicosapentaenoic acid, docosahexaenoic acid, linoleic acid, γ-linolenic acid, dihomo-γ-linolenic acid, arachidonic acid, oleic acid, erucic acid, maleic acid, fumaric acid, and dodecanoic acid, or an ester thereof.
 4. The method of producing an additive according to claim 1, wherein the relatively high molecular weight alcohol is any of pentanol, hexanol, undecanol, dodecanol, and tridecanol.
 5. The method of producing an additive according to claim 1, wherein the relatively low molecular weight alcohol is any of methanol, ethanol, propanol, and ethylene glycol.
 6. The method of producing an additive according to claim 1, wherein the surfactant is a nonionic polyether surfactant selected from polyoxyalkylene branched decyl ether, polyoxyethylene monolaurate, polyoxyethylene monooleate, and polyoxyethylene polyoxypropylene alkyl ether.
 7. The method of producing an additive according to claim 1, wherein the amine compound is any of monoethanolamine, isopropanolamine, n-propanolamine, cyclohexylamine, and derivatives thereof.
 8. The method of producing an additive according to claim 1, wherein the molar mixing ratio of the fatty acid or the relatively high molecular weight alcohol; the relatively low molecular weight alcohol; the surfactant; only the amine compound or both the amine compound and ethylene glycol; and aqueous ammonia or gaseous ammonia is 1:1.0 to 1.5:0.0 to 0.7:0.3 to 0.9:0.001 to 0.7 (molar concentration), more preferably 1:1.1 to 1.4:0.4 to 0.6:0.4 to 0.8:0.003 to 0.2 (molar concentration).
 9. An additive produced by the method according to claim 1, wherein the raw materials of the additive at least include a fatty acid or a relatively high molecular weight alcohol; a relatively low molecular weight alcohol; a surfactant; at least one of an amine compound and ethylene glycol; and aqueous ammonia or gaseous ammonia.
 10. A method of producing an additive-modified fuel oil, the additive-modified fuel oil being a water-unmixed modified fuel oil being able to be formed into a water-mixed fuel by addition of water, and the method comprising the step of: the additive according to claim 9 to a fuel oil to generate a desired additive-modified fuel oil.
 11. The method of producing an additive-modified fuel oil according to claim 10, wherein the mixing ratio of the additive and the fuel oil is 0.03 to 0.3:1 (volume), more preferably 0.05 to 0.2:1 (volume).
 12. An additive-modified fuel oil produced by the method according to claim 10, wherein the raw materials of the additive at least include a fatty acid or a relatively high molecular weight alcohol; a relatively low molecular weight alcohol; a surfactant; at least one of an amine compound and ethylene glycol; and aqueous ammonia or gaseous ammonia.
 13. A method of producing a water-mixed fuel, the method comprising the step of: adding water to the additive-modified fuel oil according to claim 12 to generate a desired water-mixed fuel.
 14. The method of producing a water-mixed fuel according to claim 13, wherein the mixing ratio of water and the additive-modified fuel oil is 0.1 to 0.8:1 (volume), more preferably 0.2 to 0.6:1 (volume).
 15. A water-mixed fuel produced by the method according to claim 13, wherein the raw materials of the additive at least include a fatty acid or a relatively high molecular weight alcohol; a relatively low molecular weight alcohol; a surfactant; only an amine compound or both an amine compound and ethylene glycol; and aqueous ammonia or gaseous ammonia; and a uniformly mixed state is stably maintained for a long period of time without causing separation between oil and water. 